The correct acknowledgment should read:
The authors are grateful for the fruitful comments of Dr. Igor Furtat related to the algorithmic portion of the work. The experimental portion (Section 3) was prepared within the framework of a subsidy granted to the National Research University Higher School of Economics by the Government of the Russian Federation for the implementation of the Global Competitiveness Program. The data fusion algorithm for reconstruction of pen traces (Section 2) was adapted to the use with the EMG data solely under support of RNF (grant 14-29-00142) in IPME RAS.
The change requested does not affect the scientific validity of the results.
Conflict of interest statement
The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.